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<div class="titlepage"><div><div><h5 class="title">
<a name="spirit.qi.reference.operator.kleene"></a><a class="link" href="kleene.html" title="Kleene Parser (*a)">Kleene Parser
          (<code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code>)</a>
</h5></div></div></div>
<h6>
<a name="spirit.qi.reference.operator.kleene.h0"></a>
            <span class="phrase"><a name="spirit.qi.reference.operator.kleene.description"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.description">Description</a>
          </h6>
<p>
            The kleene operator, <code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code>,
            is a unary operator that matches its operand zero or more times.
          </p>
<h6>
<a name="spirit.qi.reference.operator.kleene.h1"></a>
            <span class="phrase"><a name="spirit.qi.reference.operator.kleene.header"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.header">Header</a>
          </h6>
<pre class="programlisting"><span class="comment">// forwards to &lt;boost/spirit/home/qi/operator/kleene.hpp&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">qi_kleene</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<p>
            Also, see <a class="link" href="../../../structure/include.html" title="Include">Include Structure</a>.
          </p>
<h6>
<a name="spirit.qi.reference.operator.kleene.h2"></a>
            <span class="phrase"><a name="spirit.qi.reference.operator.kleene.model_of"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.model_of">Model
            of</a>
          </h6>
<div class="blockquote"><blockquote class="blockquote"><p>
              <a class="link" href="../parser_concepts/unaryparser.html" title="UnaryParser"><code class="computeroutput"><span class="identifier">UnaryParser</span></code></a>
            </p></blockquote></div>
<div class="variablelist">
<p class="title"><b>Notation</b></p>
<dl class="variablelist">
<dt><span class="term"><code class="computeroutput"><span class="identifier">a</span></code></span></dt>
<dd><p>
                  A <a class="link" href="../parser_concepts/parser.html" title="Parser"><code class="computeroutput"><span class="identifier">Parser</span></code></a>
                </p></dd>
</dl>
</div>
<h6>
<a name="spirit.qi.reference.operator.kleene.h3"></a>
            <span class="phrase"><a name="spirit.qi.reference.operator.kleene.expression_semantics"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.expression_semantics">Expression
            Semantics</a>
          </h6>
<p>
            Semantics of an expression is defined only where it differs from, or
            is not defined in <a class="link" href="../parser_concepts/unaryparser.html" title="UnaryParser"><code class="computeroutput"><span class="identifier">UnaryParser</span></code></a>.
          </p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Expression
                    </p>
                  </th>
<th>
                    <p>
                      Semantics
                    </p>
                  </th>
</tr></thead>
<tbody><tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      Match <code class="computeroutput"><span class="identifier">a</span></code> zero
                      or more times.
                    </p>
                  </td>
</tr></tbody>
</table></div>
<h6>
<a name="spirit.qi.reference.operator.kleene.h4"></a>
            <span class="phrase"><a name="spirit.qi.reference.operator.kleene.attributes"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.attributes">Attributes</a>
          </h6>
<p>
            See <a class="link" href="../../quick_reference/compound_attribute_rules.html#spirit.qi.quick_reference.compound_attribute_rules.notation">Compound
            Attribute Notation</a>.
          </p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Expression
                    </p>
                  </th>
<th>
                    <p>
                      Attribute
                    </p>
                  </th>
</tr></thead>
<tbody><tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="special">*</span><span class="identifier">a</span></code>
                    </p>
                  </td>
<td>
                    <p>
</p>
<pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="identifier">a</span><span class="special">:</span> <span class="identifier">A</span> <span class="special">--&gt;</span> <span class="special">*</span><span class="identifier">a</span><span class="special">:</span> <span class="identifier">vector</span><span class="special">&lt;</span><span class="identifier">A</span><span class="special">&gt;</span>
<span class="identifier">a</span><span class="special">:</span> <span class="identifier">Unused</span> <span class="special">--&gt;</span> <span class="special">*</span><span class="identifier">a</span><span class="special">:</span> <span class="identifier">Unused</span></pre>
<p>
                    </p>
                  </td>
</tr></tbody>
</table></div>
<h6>
<a name="spirit.qi.reference.operator.kleene.h5"></a>
            <span class="phrase"><a name="spirit.qi.reference.operator.kleene.complexity"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.complexity">Complexity</a>
          </h6>
<div class="blockquote"><blockquote class="blockquote"><p>
              The overall complexity of the Kleene star is defined by the complexity
              of its subject, <code class="computeroutput"><span class="identifier">a</span></code>,
              multiplied by the number of repetitions. The complexity of the Kleene
              star itself is O(N), where N is the number successful repetitions.
            </p></blockquote></div>
<h6>
<a name="spirit.qi.reference.operator.kleene.h6"></a>
            <span class="phrase"><a name="spirit.qi.reference.operator.kleene.example"></a></span><a class="link" href="kleene.html#spirit.qi.reference.operator.kleene.example">Example</a>
          </h6>
<div class="note"><table border="0" summary="Note">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td>
<th align="left">Note</th>
</tr>
<tr><td align="left" valign="top"><p>
              The test harness for the example(s) below is presented in the <a class="link" href="../basics.html#spirit.qi.reference.basics.examples">Basics Examples</a>
              section.
            </p></td></tr>
</table></div>
<p>
            Some using declarations:
          </p>
<p>
</p>
<pre class="programlisting"><span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">qi</span><span class="special">::</span><span class="identifier">int_</span><span class="special">;</span>
</pre>
<p>
          </p>
<p>
            Parse a comma separated list of numbers and put them in a vector:
          </p>
<p>
</p>
<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="identifier">attr</span><span class="special">;</span>
<span class="identifier">test_phrase_parser_attr</span><span class="special">(</span>
    <span class="string">"111, 222, 333, 444, 555"</span><span class="special">,</span> <span class="identifier">int_</span> <span class="special">&gt;&gt;</span> <span class="special">*(</span><span class="char">','</span> <span class="special">&gt;&gt;</span> <span class="identifier">int_</span><span class="special">),</span> <span class="identifier">attr</span><span class="special">);</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span>
    <span class="special">&lt;&lt;</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">0</span><span class="special">]</span> <span class="special">&lt;&lt;</span> <span class="char">','</span> <span class="special">&lt;&lt;</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">1</span><span class="special">]</span> <span class="special">&lt;&lt;</span> <span class="char">','</span> <span class="special">&lt;&lt;</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">2</span><span class="special">]</span> <span class="special">&lt;&lt;</span> <span class="char">','</span>
    <span class="special">&lt;&lt;</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">3</span><span class="special">]</span> <span class="special">&lt;&lt;</span> <span class="char">','</span> <span class="special">&lt;&lt;</span> <span class="identifier">attr</span><span class="special">[</span><span class="number">4</span><span class="special">]</span>
    <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
</pre>
<p>
          </p>
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<td align="right"><div class="copyright-footer">Copyright © 2001-2011 Joel de Guzman, Hartmut Kaiser<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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